JPS61139021A - Temperature measurement of mbe base board - Google Patents

Temperature measurement of mbe base board

Info

Publication number
JPS61139021A
JPS61139021A JP26103184A JP26103184A JPS61139021A JP S61139021 A JPS61139021 A JP S61139021A JP 26103184 A JP26103184 A JP 26103184A JP 26103184 A JP26103184 A JP 26103184A JP S61139021 A JPS61139021 A JP S61139021A
Authority
JP
Japan
Prior art keywords
mbe
layer
substrate
base board
infra
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP26103184A
Other languages
Japanese (ja)
Inventor
Yuuji Ishida
祐士 石田
Masahito Mushigami
雅人 虫上
Hayamizu Fukada
深田　速水
Naotaro Nakada
直太郎 中田
Haruo Tanaka
田中　治夫
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Rohm Co Ltd
Original Assignee
Rohm Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Rohm Co Ltd filed Critical Rohm Co Ltd
Priority to JP26103184A priority Critical patent/JPS61139021A/en
Publication of JPS61139021A publication Critical patent/JPS61139021A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02612—Formation types
    • H01L21/02617—Deposition types
    • H01L21/02631—Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Radiation Pyrometers (AREA)
  • Physical Deposition Of Substances That Are Components Of Semiconductor Devices (AREA)

Abstract

PURPOSE:To make it possible to accurately measure the temperature of the growing base board for MBE, by a method wherein infra-red ray irradiated from the heater is shielded by the infra-red ray transmission preventive layer which is coated on the back side of the plane on which the MBE base board layer is to be grown. CONSTITUTION:The back side on the plane 22 on which the layer on the MBE base board 20 is to be grown is coated with the reaction prevention layer 23, and further, this reaction preventive layer 23 is coated with infra-red ray transmission preventive layer 24 which prevent the transmission of the infra-red ray irradiated from parts other than the MBE base board 20. The MBE base board 20 is mounted on the base board bench 3 within which a heater is provide as a heating means for the MBE base board so that the reaction preventive layer 23 and the infra-red ray transmission preventive layer 24 face to the heater 33 and are heated until the suitable temperature for the growth of the layer is reached. At this time, the infra-red ray irradiated from the plane 22 on the MBE base board 20 is detected through the view port 10 with an infra-red ray pyro-meter 11, and the intensity of the infra-red ray is converted into the electricity and converted so as to obtain the temperature of the MBE base board 20 on which the layer is under growth.

Description

【発明の詳細な説明】 （イ）産業上の利用分野 この発明は、表面にＭＢＥ　（分子線エピタキシャル成
長）装置で層が形成されるＭＢＥ用基板の温度測定方法
に関する。DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a method for measuring the temperature of a substrate for MBE on whose surface a layer is formed using an MBE (molecular beam epitaxial growth) apparatus.

（ロ）従来技術 半導体レーザ等の製作において、各成長層の厚さを精度
良く形成する手段としてＭＢＥ法が有効である。しかる
にＭＢＥ法において、所望の特質をもった層を再現性良
（成長させるには、結晶成長条件である成長途中におけ
る基板の温度を測定制御することが重要な要件となる。(b) Prior Art In the production of semiconductor lasers and the like, the MBE method is effective as a means of precisely forming the thickness of each growth layer. However, in the MBE method, in order to grow a layer with desired characteristics with good reproducibility, it is important to measure and control the temperature of the substrate during growth, which is a crystal growth condition.

第３図はＭＢＥ装置の構成を示す模式図であり、ｌは内
部が超高真空に引かれるチャンバ、２は主表面に成長層
が形成されるＭＢＥ用基板であり基板台３に装着されて
いる。４はＭＢＥ用基板２に分子線の形で入射されるＧ
ａ、Ａｌ、Ａｓ等の材料供給源である。５は前記材料供
給源４の外周に巻回−されたヒータ線、６は前記材料供
給源４の前面に配設されたシャッタである。７は電子銃
、８は質量分析器、９はＲＨＢＥＤ　（高速反射電子線
回折の略称）スクリーン、１０ばビューボート、１１は
ＭＢＥ用基板２の温度測定用の赤外線パイロメータであ
る。但し、図例の基板台３は、ＭＢＥ用基板２の加熱制
御を容易にするため、特願昭５９−２２３１３にみられ
るようにＭＢＥ用基板２が螺子３７および押圧部材３６
で支持される基板台ブロック３１にはＭＢＦ、用基板２
よりも僅かに小径の開孔部３８が形成され、ヒータ３３
でＭＢＥ用基板２を直接加熱できるように改良が加えら
れたものが利用されている。そして上記基板台３に従来
のＭＢＥ用基板２が第２図の如（装着される。FIG. 3 is a schematic diagram showing the configuration of the MBE apparatus, where l is a chamber whose interior is drawn to an ultra-high vacuum, and 2 is an MBE substrate on which a growth layer is formed on the main surface, which is mounted on a substrate stand 3. There is. 4 is G incident on the MBE substrate 2 in the form of a molecular beam.
It is a source of materials such as a, Al, and As. 5 is a heater wire wound around the outer periphery of the material supply source 4, and 6 is a shutter disposed in front of the material supply source 4. 7 is an electron gun, 8 is a mass spectrometer, 9 is an RHBED (abbreviation for high-speed reflection electron diffraction) screen, 10 is a view boat, and 11 is an infrared pyrometer for measuring the temperature of the MBE substrate 2. However, in the illustrated example substrate stand 3, in order to facilitate heating control of the MBE substrate 2, the MBE substrate 2 has screws 37 and a pressing member 36 as seen in Japanese Patent Application No. 59-22313.
The board stand block 31 supported by the MBF, the board 2
An opening 38 having a slightly smaller diameter than that of the heater 33 is formed.
An improved device is used in which the MBE substrate 2 can be directly heated. A conventional MBE substrate 2 is mounted on the substrate stand 3 as shown in FIG.

しかして、従来のＭＢＥ用基板の籠度測定方法は、上記
の如く構成の装置を用い、成長途中のＭＢＥ用基板２か
ら発せられる赤外線の強度をビューポート１０を通し、
赤外線パイロメータ１１にて前記ＭＢＥ用基板２の温度
を測定するものである。Therefore, the conventional method for measuring the compactness of MBE substrates uses a device configured as described above, and measures the intensity of infrared rays emitted from the MBE substrate 2 during growth through the view port 10.
The temperature of the MBE substrate 2 is measured by an infrared pyrometer 11.

この方法では、基板台ブロック３１に熱電対を設けて測
定する方法よりも精度が良いが、その反面以下のような
不都合を生じる。即ちＭＢＥ用基板としてＧａＡｓ、Ｓ
ｉ、ＩｎＰ等の赤外線の透過率の大きい材質の基板を用
いる場合、赤外線パイロメータが感受する赤外線にはＭ
−ＢＥ用基板２から発せられるものに、ヒータ３３から
発せられＭＢＥ用基板２を透過したものが加わる可能性
がありＭＢＥ用基板の温度を正確に測定しているとは言
えない。This method has better accuracy than the method of measuring by providing a thermocouple on the substrate table block 31, but on the other hand, it causes the following disadvantages. That is, as a substrate for MBE, GaAs, S
When using a substrate made of a material with high infrared transmittance, such as InP, the infrared rays detected by the infrared pyrometer contain M
- There is a possibility that the radiation emitted from the heater 33 and transmitted through the MBE substrate 2 is added to the radiation emitted from the BE substrate 2, so it cannot be said that the temperature of the MBE substrate is accurately measured.

そこで、本件出願人は上記不具合を改善するために特願
昭５９−１６４００８号を提案している。Therefore, the applicant has proposed Japanese Patent Application No. 164008/1983 in order to improve the above-mentioned problems.

それは、層が成長される面の背面側に赤外線を透過しな
い高融点金属層を被着したＭＢＥ用基板を用いることに
より、ＭＢＥ用基板からのみ発する赤外線を赤外線パイ
ロメータでもって測定するようになしたものである。By using an MBE substrate with a high melting point metal layer that does not transmit infrared rays on the back side of the surface on which the layer is grown, the infrared rays emitted only from the MBE substrate can be measured using an infrared pyrometer. It is something.

このようにした場合、比較的低温例えば〜７００℃位ま
でであれば確かに成長途中のＭＢＥ用基板の温度を正確
に測定することができる。しかしながら、比較的高温例
えば７００℃〜８００℃位の間において層を成長させる
場合に該ＭＢＥ用基板としてＧａＡｓ基板を用いたとき
、該ＣａＡｓ基板に被着した高融点金属層であるＭＯ３
Ｔｉ等が該ＧａＡｓ基板と熱反応して赤外線透過率が変
化する恐れがあるという問題点が残っている。In this case, the temperature of the MBE substrate in the middle of growth can be accurately measured at relatively low temperatures, for example, up to about 700°C. However, when a GaAs substrate is used as the MBE substrate when growing a layer at a relatively high temperature, for example, between 700°C and 800°C, the high melting point metal layer deposited on the CaAs substrate is
There remains a problem that Ti and the like may thermally react with the GaAs substrate, resulting in a change in infrared transmittance.

（ハ）目的 この発明は上記事情に鑑みてなされたもので、眉の成長
途中の温度に関係なくＭＢＥ用基板の温度を正確に測定
しうるＭＢＥ用基板の温度測定方法を提供することにあ
る。(C) Purpose This invention was made in view of the above circumstances, and an object thereof is to provide a temperature measuring method for an MBE substrate that can accurately measure the temperature of an MBE substrate regardless of the temperature during the growth of eyebrows. .

（ニ）構成 この発明に係るＭＢＥ用基板の温度測定方法の特徴とす
る処は、層を成長すべき面側の背面にＭＢＥ用基板と熱
反応しない反応防止層が被着されると共にその上に該Ｍ
ＢＥ用基板以外から射出される赤外線を前記層を成長す
べき面側に透過させない赤外線透過防止層が被着された
ＭＢＥ用基板を、前記反応防止層および赤外線透過防止
層が被着された面側より加熱し、前記層を成長すべき面
側に配備したパイロメータでもって該ＭＢＥ用基板より
射出される赤外線の強度を検知することにある。(d) Structure The method for measuring the temperature of an MBE substrate according to the present invention is characterized in that a reaction prevention layer that does not thermally react with the MBE substrate is coated on the back side of the surface on which a layer is to be grown, and a reaction prevention layer that does not thermally react with the MBE substrate is applied. The M
An MBE substrate coated with an infrared transmission prevention layer that does not transmit infrared rays emitted from a source other than the BE substrate to the side on which the layer is to be grown is attached to the side on which the reaction prevention layer and the infrared transmission prevention layer are coated. The purpose is to detect the intensity of infrared rays emitted from the MBE substrate by heating it from the side and using a pyrometer placed on the side on which the layer is to be grown.

（ホ）実施例 第１図はこの発明において使用されるＭＢＥ用基板２０
を第３図の基板台３に装着したところを示す拡大断面図
であり、第２図と同一部分には同じ符号を付しである。(E) Embodiment FIG. 1 shows an MBE substrate 20 used in this invention.
3 is an enlarged sectional view showing the circuit board mounted on the substrate stand 3 of FIG. 3, and the same parts as in FIG. 2 are given the same reference numerals.

ＭＢＥ用基板２０の層を成長すべき面２２側の背面には
、該基板２０と反応しないようなものからなる反応防止
層２３が被着されると共に更にこの反応防止層２３の上
には、該ＭＢＥ用基板基板２０以外発する赤外線を透過
させない赤外線透過防止層２４が蒸着、スパッタリング
等により被着されている。A reaction prevention layer 23 made of a material that does not react with the substrate 20 is deposited on the back side of the surface 22 of the MBE substrate 20 on which the layer is to be grown, and further on this reaction prevention layer 23, An infrared transmission prevention layer 24 that does not transmit infrared rays emitted from other than the MBE substrate 20 is deposited by vapor deposition, sputtering, or the like.

具体的には、反応防止層２３として例えばｐ−ｃＶＤ等
でもって生成されるＳｉ３　Ｎ　４膜又はＳｉＯ２膜等
がある。さらに赤外線透過防止層２４としては、チャン
バ１内の分子汚染を避けるためチャンバ１内に既存する
金属、例えば、基板台３の通常の材質であるＭｏ　　（
モリブデン）の他、Ｔａ　　（タンタル）、Ｗ（タング
ステン）、Ｔｉ（チタン）を用いるのが望ましい。Specifically, the reaction prevention layer 23 may be a Si3N4 film or a SiO2 film produced by p-cVD or the like. Further, as the infrared transmission prevention layer 24, in order to avoid molecular contamination in the chamber 1, a metal existing in the chamber 1, for example, Mo(
It is desirable to use Ta (tantalum), W (tungsten), and Ti (titanium) in addition to molybdenum.

上記の如く処理を施したＭＢＥ用基板２０の面２２側に
層を成長させるにあたっては、第３図に示した従来から
のＭＢＥ装置を同等変更することなく用いることができ
る。但し基板台３に本件実施例によるＭＢＥ用基板２０
を装着すべきことは言うまでもない。To grow a layer on the side 22 of the MBE substrate 20 treated as described above, the conventional MBE apparatus shown in FIG. 3 can be used without any modification. However, the MBE board 20 according to this embodiment is mounted on the board stand 3.
It goes without saying that you should wear one.

しかるに、成長途中のＭＢＥ用基板２０の温度測定方法
を第３図を参考に説明すると、ＭＢＥ用基板の加熱手段
であるヒータ３３が内部に設けられた基板台３には、反
応防止層２３および赤外線透過防止Ｎ２４がヒータ３３
に相対向するようにＭＢＥ用基板２０が装着され、層の
成長にあたって適宜温度になるまで加熱される。このと
きＭＢＥ用基板２０の面２２から射出される赤外線をビ
ューポート１０を通して赤外線パイロメータ１１で検知
し、赤外線の強度を電気変換することにより層の成長途
中のＭＢＥ用基板２０の温度を換算して求める。However, to explain the method of measuring the temperature of the MBE substrate 20 during growth with reference to FIG. 3, the reaction prevention layer 23 and Infrared transmission prevention N24 is heater 33
The MBE substrate 20 is mounted so as to face the substrate 20 and heated to an appropriate temperature for layer growth. At this time, the infrared rays emitted from the surface 22 of the MBE substrate 20 are detected by the infrared pyrometer 11 through the view port 10, and the intensity of the infrared rays is electrically converted to convert the temperature of the MBE substrate 20 during layer growth. demand.

（へ）効果 この発明によれば、ＭＢＥ用基板の層を成長すべき面の
背面側に被着された赤外線透過防止層でもって加熱用ヒ
ータから射出される赤外線を遮断するから、パイロメー
タが感受する赤外線はＭＢＥ用基板から射出されるもの
に限定され成長途中のＭＢＥ用基板の温度を正確に測定
することができる。その結果、成長条件の制御の精度が
向上する。しかも、前記ＭＢＥ用基板と赤外線透過防止
層との間に反応防止層を介在させているから、比較的低
温（例えば７００℃以下）においては勿論のこと、比較
的高温（例えば７００°Ｃ以上）で層を成長させる場合
に起こり易い該ＭＢＥ用基板と赤外線透過防止層との熱
反応を抑制させることができる。即ち、成長途中におけ
る測温条件の変化を無（することができる。その結果、
長時間の成長においても正確な温度測定が可能となり、
高品質なレーザウェハを再現性良く形成することができ
る。(F) Effect According to the present invention, the infrared rays emitted from the heater are blocked by the infrared rays transmission prevention layer coated on the back side of the surface on which the layer of the MBE substrate is grown, so that the pyrometer is sensitive to the infrared rays emitted from the heater. The infrared rays emitted from the MBE substrate are limited to those emitted from the MBE substrate, and the temperature of the MBE substrate during growth can be accurately measured. As a result, the precision of controlling growth conditions is improved. Moreover, since the reaction prevention layer is interposed between the MBE substrate and the infrared transmission prevention layer, it can be used not only at relatively low temperatures (e.g., 700°C or less) but also at relatively high temperatures (e.g., 700°C or more). It is possible to suppress the thermal reaction between the MBE substrate and the infrared transmission prevention layer, which is likely to occur when a layer is grown using the method. In other words, it is possible to eliminate changes in temperature measurement conditions during growth.As a result,
Accurate temperature measurement is possible even during long-term growth.
High quality laser wafers can be formed with good reproducibility.

なお、本発明の効果が顕著に現れるので基板台ブロック
に開孔部を設けた改良型の基板台を配備したＭＢＥ装置
を例にとって説明したが基板台ブロックに開孔部を設け
ない基板台を用いる場合にも本発明の効果は現れる。即
ちヒータで加熱された基板台ブロックから射出される赤
外線をパイロメータが感受することが避けられるからで
ある。Note that, since the effects of the present invention can be clearly seen, an explanation has been given of an MBE apparatus equipped with an improved type of substrate stand in which an opening is provided in the substrate stand block, but a substrate stand without openings in the substrate stand block is explained. The effects of the present invention also appear when used. That is, this prevents the pyrometer from sensing infrared rays emitted from the substrate table block heated by the heater.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図はこの発明において使用されるＭＢＥ用基板２０
を第３図の基板台３に装着したところを示す拡大断面図
、第２図は従来のＭＢＥ用基板２を第３図の基板台３に
装着したところを示す拡大断面図、第３図はＭＢＥ装置
の構成を略示した模式１１・・・赤外線パイロメータ、
２０・・・ＭＢＥ用基板、２３・・・反応防止層、２４
・・・赤外線透過防止層。 特許出願人　　　　　ローム株式会社 代理人　　弁理士　　大　西　孝　治 第１図 第２図FIG. 1 shows an MBE substrate 20 used in this invention.
FIG. 2 is an enlarged cross-sectional view showing the conventional MBE board 2 mounted on the board stand 3 of FIG. 3, and FIG. Schematic 11 schematically showing the configuration of the MBE device...infrared pyrometer,
20... MBE substrate, 23... Reaction prevention layer, 24
...Infrared transmission prevention layer. Patent Applicant: ROHM Co., Ltd. Agent, Patent Attorney: Takaharu Ohnishi Figure 1 Figure 2

Claims (1)

【特許請求の範囲】[Claims] （１）層を成長すべき面側の背面にＭＢＥ用基板と熱反
応しない反応防止層が被着されると共にその上に該ＭＢ
Ｅ用基板以外から射出される赤外線を前記層を成長すべ
き面側に透過させない赤外線透過防止層が被着されたＭ
ＢＥ用基板を、前記反応防止層および赤外線透過防止層
が被着された面側より加熱し、前記層を成長すべき面側
に配備したパイロメータでもって該ＭＢＥ用基板より射
出される赤外線の強度を検知することを特徴とするＭＢ
Ｅ用基板の温度測定方法。(1) A reaction prevention layer that does not thermally react with the MBE substrate is deposited on the back side of the surface on which the layer is to be grown, and the MB
M coated with an infrared transmission prevention layer that does not transmit infrared rays emitted from sources other than the E substrate to the side on which the layer is to be grown.
The BE substrate is heated from the side on which the reaction prevention layer and the infrared transmission prevention layer are applied, and the intensity of infrared rays emitted from the MBE substrate is measured using a pyrometer placed on the side where the layer is to be grown. MB characterized by detecting
How to measure the temperature of the E board.
JP26103184A 1984-12-10 1984-12-10 Temperature measurement of mbe base board Pending JPS61139021A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP26103184A JPS61139021A (en) 1984-12-10 1984-12-10 Temperature measurement of mbe base board

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP26103184A JPS61139021A (en) 1984-12-10 1984-12-10 Temperature measurement of mbe base board

Publications (1)

Publication Number Publication Date
JPS61139021A true JPS61139021A (en) 1986-06-26

Family

ID=17356086

Family Applications (1)

Application Number Title Priority Date Filing Date
JP26103184A Pending JPS61139021A (en) 1984-12-10 1984-12-10 Temperature measurement of mbe base board

Country Status (1)

Country Link
JP (1) JPS61139021A (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58190897A (en) * 1982-04-30 1983-11-07 Fujitsu Ltd Method for growing crystal by molecular beam
JPS58197719A (en) * 1982-05-13 1983-11-17 Ricoh Co Ltd Substrate heating structure and heating process
JPS5992998A (en) * 1982-11-19 1984-05-29 Agency Of Ind Science & Technol Method for growing crystal using molecular beam
JPS60240119A (en) * 1984-05-15 1985-11-29 Fujitsu Ltd Molecular beam crystal growth

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58190897A (en) * 1982-04-30 1983-11-07 Fujitsu Ltd Method for growing crystal by molecular beam
JPS58197719A (en) * 1982-05-13 1983-11-17 Ricoh Co Ltd Substrate heating structure and heating process
JPS5992998A (en) * 1982-11-19 1984-05-29 Agency Of Ind Science & Technol Method for growing crystal using molecular beam
JPS60240119A (en) * 1984-05-15 1985-11-29 Fujitsu Ltd Molecular beam crystal growth

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